摘要
通过了解湘西地区猕猴桃溃疡病致病菌分类地位和基因类型,初步探讨其致病的分子机理。采用纯培养法分离猕猴桃溃疡病菌;基于16S~23S rRNA基因内转录间隔序列进行病原菌的系统发育分析;通过基因组测序和生物信息学分析解析其致病的分子机理。从“米良1号”和“红阳”猕猴桃感病枝条中分离获得5株溃疡病菌,编号为L211、L212、L321、L322、L323;通过形态特征和16S~23S rRNA基因内转录间隔序列分析,鉴定5株细菌均为丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv.actinidae,Psa)。以菌株L211为代表进行体外猕猴桃枝条接种实验表明能引起典型溃疡病症状。通过菌株L211的全基因组测序和生物信息学分析,获得5741条基因数目,长5412072 bp;基因功能注释发现菌株L211携带121种毒力因子、71个植物互作因子和77个耐药基因;同时,基因组单核苷酸多态性分析发现病原菌L211为基因Ⅲ型Psa。引起湘西地区猕猴桃溃疡病的病原菌是丁香假单胞菌猕猴桃致病变种基因Ⅲ型,与国内外报道的引起猕猴桃溃疡病大流行的致病菌一致。猕猴桃溃疡病发病原因可能是病原菌的多种毒力基因和互作基因协同作用的结果。
Taxonomic status and genotypes of kiwifruit canker bacteria in western Hunan was clarified and prelimina⁃rily explored the molecular mechanism of the pathogenesis.Bacteria pathogens of kiwifruit were isolated by culture⁃de⁃pendent methods,and identified based on sequence analysis of the internal transcribed spacer of 16S⁃23S rRNA gene.Genome sequencing and bio⁃information analysis were used to explore the molecular mechanism of the pathogenic bac⁃terium.The results showed that five strains of bacterial pathogens,named after strain L211,L212,L321,L322,L323,were isolated from the infected branches of the kiwifruit"Miliang No.1"and"Hong Yang"in western Hunan,and these were identified as Pseudomonas syringae pv.actinidae(Psa).In vitro branching inoculation experiments usingthe L211 strain as a representative showed that it could cause typical kiwifruit canker disease.Following whole genome sequencing of strain L211 and bioinformation analysis,5741 genes with a total length of 5412072 bp were obtained,L211 strain was found to harbor 121 virulence factors,71 plant⁃interactions factors and 77 drug⁃resistance genes.Single nucleotide polymorphism analysis indicated that the L211 strain belonged to the Psa biovarⅢ.To con⁃clude,Psa biovarⅢis the leading cause of kiwifruit canker disease in western Hunan,which is the same pathogenic bacterium bringing about global pandemic kiwifruit canker as reported home and abroad.The pathogenesis of kiwifruit canker disease may be the result of the synergistic action of multiple virulence and reciprocal genes of the pathogen.
作者
杨睿
汪琳罗沙
姚迪
唐蕴哲
张婧一
彭清忠
YANG Rui;WANG Linluo-sha;YAO Di;TANG Yun-zhe;ZHANG Jing-yi;PENG Qing-zhong(Coll.of Bio-Res.&Environ.Sci.,Jishou Uni.,Jishou 416000)
出处
《微生物学杂志》
CAS
CSCD
北大核心
2024年第1期58-67,共10页
Journal of Microbiology
基金
国家自然科学基金项目(32160009)
湖南省重点研发计划项目(2022NK2055)。
关键词
猕猴桃溃疡病
丁香假单胞菌猕猴桃致病变种
鉴定
全基因组测序
致病机理
kiwifruit canker disease
Pseudomonas syringae pv.Actinidae
identification
whole genome sequencing
pathogenic mechanism
